Traditional chopsticks are formed of wood. Of course, wood is a porous material and consequently the re-use of wooden chopsticks, particularly by other persons such as in a restaurant or other public setting, creates potential health problems. Also, as wood has become increasingly more expensive, it would be desirable to provide disposable chopsticks which are less costly than wooden chopsticks.
It has been proposed to form chopsticks of molded plastic, i.e. injection molded plastic. The Dawes U.S. Pat. No. 3,186,749 discloses molded plastic chopsticks; also see the Hosak-Robb U.S. Pat. 4,707,922. One problem with plastic, however, is that its surface is exceedingly slippery, and thus plastic chopsticks are difficult to use, particularly for those who do not have substantial experience in eating with these utensils. This problem is solved by Dawes by forming tip end gripping faces which are knurled or otherwise roughened to provide a better grip on the food which is intended to be grasped. However, two problems exist with regard to the Dawes solution, namely the roughening operation requires a additional processing step thus increasing the cost of manufacture, and furthermore this solution is particularly adapted to the spring-connected chopsticks of Dawes which are clipped together so that the inclined facing surfaces, roughened as indicated above, always come into contact with one another.
Also of interest is the Young U.S. Pat. No. 4,312,530 which shows a hinged chopsticks assembly and the McGogy U.S. Pat. No. 2,711,339 entitled "Tongs" which shows a pair of chopsticks held together with a spring metal holder. In both of these constructions, the lower ends of the chopsticks are provided with corrugated ridges or serrations, presumably for the purpose of increasing friction to facilitate the use of these chopsticks constructions in order to better hold the food therebetween without slippage. In all these cases, however, the roughened or serrated portion is limited only to the lowermost portion of each stick, and only on predetermined facing surfaces which are fixed in each case by the spring guide or hinge construction. These configurations are unsuitable for unhinged or unconnected chopsticks used in the conventional manner.
In addition to the problems mentioned above, the use of plastic in the manufacture of chopsticks has resulted in two further problems. First, as already mentioned above, the public has become increasingly concerned with diseases such as hepatitis and salmonella, and therefore even eating utensils which are more easily cleaned than those formed of wood are of increasing concern. While plastic chopsticks can of course be more easily washed, many plastics including the least expensive plastics are not heat tolerant. To be able to wash plastic chopsticks in an effective manner requires the use of very hot water, and certain plastics cannot tolerate these conditions. Second, due to the rising cost of plastics, the conventional plastic chopsticks are too expensive for a single use. Therefore, the need exists for chopsticks which are sufficiently inexpensive so that they can be thrown away after one use.